X-ray photoelectron spectroscopy (XPS) has been employed to investigate the protonation degree of polyaniline doped with sulfosalicylic acid (PAni-SSA) obtained by different synthetic methods. The protonation degree has been compared to electrical conductivity. Prepared PAni-SSA through the redoping process in an agate mortar displays conductivity values within the range of 1S/cm. Protonation degree of synthesized PAni-SSA by aqueous dispersion polymerization of aniline in the presence of SSA is higher than 50 %, indicating that a substantial portion of amine units have also been protonated. The C/N and S/N molar ratios obtained by XPS analysis indicate that the polyaniline chains obtained by aqueous dispersion polymerization are protonated by both sulfate anions.

A chemical oxidative polymerization of aniline sulfosalicylic acid (ANISSA) and aniline sulfate acid (ANIH2SO4) was performed in an aqueous solution. A co-doped polyaniline (PANI) was thus obtained, a higher conductivity than the insoluble H2SO4-doped PANI compressed pellet, and much higher conductivity than that prepared from pure ANISSA. The PANI doped with SSA and H2SO4 was characterized using Fourier-transform infrared spectra (FTIR), Fourier-transform Raman spectra (FT-Raman), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The investigation reveals that SSA and H2SO4 as dopant not only enhances crystallinity of polyaniline but also stability of polyaniline.

Conductive polyaniline/boron carbide (PANI/B4C) composites have been synthesized by in-situ polymerization of aniline in the presence of B4C particles. The structure and thermal stability of obtained composites were characterized by FTIR, XRD and TGA. The results showed that PANI and B4C particles were not simply blended, and a strong interaction existed at the interface of B4C and PANI. In the PANI/B4C composite, the degree crystalline of PANI increased and diffraction pattern of B4C was all but of amorphous. And that the composites were more thermally stable than that of the pure PANI. Electrical conductivity measurements indicated that the conductivity of PANI/B4C composites was much higher than that of the pure PANI and the maximum conductivity obtained was 35.6 S•cm-1 at 20 wt% of B4C.